Compiz - What effect I really don't needI don't think you really "need" any effects to have a working desktop. I think this question is rather broad and you might get better answers if you can tell us your specs...

Windows 7 side by side with UbuntuWindows doesn't understand the Linux file system, and if you look at it under Disk Management, as far as Windows is concerned it is an empty partition. There is third party software that makes you able to view Linux Partitions from Windows, I don't know if this makes any difference or not, but in my experience, Windows just does not play nice with Linux.